8-O-tert-butyl 1-O-methyl octanedioate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Di-tert-butyl dicarboxylate (9.58 mL, 41.7 mmol) and 4-dimethylaminopyridine (1.02 g, 0.34 mmol) were successively added to a tert-butanol solution (56 mL) of 7-methoxycarbonylheptanoic acid (1) (5.00 mL, 5.24 g, 27.8 mmol) at room temperature under the argon atmosphere, and the mixture was stirred at room temperature for 1 hour. A 0.2 N hydrochloric acid solution (20 mL) was added to the reaction solution to make the mixture weakly acidic, and the reaction solution was concentrated to about ⅓ volume, and extracted with chloroform (50 mL) three times. The organic layer was washed with saturated brine (50 mL), dried over sodium sulfate, and concentrated. The resulting brown oily crude product (6.5 g) was separated and purified by silica gel column chromatography (hexane:ethyl acetate=10:1) to obtain t-butyl-7-methoxycarbonylheptanoate (2) as a colorless liquid substance (5.58 g, 82%). the reaction solution was concentrated to about ⅓ volume extracted with chloroform (50 mL) three times The organic layer was washed with saturated brine (50 mL) dried over sodium sulfate concentrated The resulting brown oily crude product (6.5 g) was separated purified by silica gel column chromatography (hexane:ethyl acetate=10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Di-tert-butyl dicarboxylate (9.58 mL, 41.7 mmol) and 4-dimethylaminopyridine (1.02 g, 0.34 mmol) were successively added to a tert-butanol solution (56 mL) of 7-methoxycarbonylheptanoic acid (1) (5.00 mL, 5.24 g, 27.8 mmol) at room temperature under the argon atmosphere, and the mixture was stirred at room temperature for 1 hour. A 0.2 N hydrochloric acid solution (20 mL) was added to the reaction solution to make the mixture weakly acidic, and the reaction solution was concentrated to about ⅓ volume, and extracted with chloroform (50 mL) three times. The organic layer was washed with saturated brine (50 mL), dried over sodium sulfate, and concentrated. The resulting brown oily crude product (6.5 g) was separated and purified by silica gel column chromatography (hexane:ethyl acetate=10:1) to obtain t-butyl-7-methoxycarbonylheptanoate (2) as a colorless liquid substance (5.58 g, 82%). the reaction solution was concentrated to about ⅓ volume extracted with chloroform (50 mL) three times The organic layer was washed with saturated brine (50 mL) dried over sodium sulfate concentrated The resulting brown oily crude product (6.5 g) was separated purified by silica gel column chromatography (hexane:ethyl acetate=10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Di-tert-butyl dicarboxylate (9.58 mL, 41.7 mmol) and 4-dimethylaminopyridine (1.02 g, 0.34 mmol) were successively added to a tert-butanol solution (56 mL) of 7-methoxycarbonylheptanoic acid (1) (5.00 mL, 5.24 g, 27.8 mmol) at room temperature under the argon atmosphere, and the mixture was stirred at room temperature for 1 hour. A 0.2 N hydrochloric acid solution (20 mL) was added to the reaction solution to make the mixture weakly acidic, and the reaction solution was concentrated to about ⅓ volume, and extracted with chloroform (50 mL) three times. The organic layer was washed with saturated brine (50 mL), dried over sodium sulfate, and concentrated. The resulting brown oily crude product (6.5 g) was separated and purified by silica gel column chromatography (hexane:ethyl acetate=10:1) to obtain t-butyl-7-methoxycarbonylheptanoate (2) as a colorless liquid substance (5.58 g, 82%). the reaction solution was concentrated to about ⅓ volume extracted with chloroform (50 mL) three times The organic layer was washed with saturated brine (50 mL) dried over sodium sulfate concentrated The resulting brown oily crude product (6.5 g) was separated purified by silica gel column chromatography (hexane:ethyl acetate=10:1)